Download - M.sc (Contects) (Lecture-1)
"Prof Dr. Suhail Aftab Qureshi" 1
POWER CIRCUIT BREAKERSAND
SUBSTATIONS
“Prof Dr. Suhail Aftab Qureshi”
BYBY
"Prof Dr. Suhail Aftab Qureshi" 2
Classification of circuit Breaker and isolators,Terminology’ Circuit Breakers, Arcs, SF6 Switchgear & Circuit Breakers, Air Blast Circuit Breakers, oil Circuit Breaker, Special Purpose Circuit Breakers & Isolators, D.C Circuit Breakers,Breakers requirement, Testing, Switchgear Testing, Synthetic Testing, Substation Layout and Design,
Power Circuit Breakers and Substations
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BOOKSBOOKS
1.1. "Advances in H.V insulation and Arc "Advances in H.V insulation and Arc interruption'in SFinterruption'in SF66 and Vacuum", and Vacuum",
By V.N. Maller & M.S Naidu.By V.N. Maller & M.S Naidu.
2.2. "Power Circuit Breakers Theory and Design", "Power Circuit Breakers Theory and Design",
By C.H. Flurscheim.By C.H. Flurscheim.
3.3. "ELECTRICAL SUBSTATION", ENGINEERING "ELECTRICAL SUBSTATION", ENGINEERING AND PRACTICE, AND PRACTICE,
BY S RAO.BY S RAO.
Power Circuit Breakers and Substations
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1.1. Classification of Circuit Breakers and Classification of Circuit Breakers and IsolatorsIsolators
a.a. IntroductionIntroductionb.b. Circuit Breakers, Switching Isolators, Circuit Breakers, Switching Isolators,
Isolator or DisconnectorsIsolator or Disconnectors
Contents
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2. Terminology:
a. Service Voltageb. Recovery Voltagec. Restriking Voltage (TRV)d. Interruption with Restrikese. Prospective Currentf. Prospective Breaking Currentg. Breaking Capacityh. Symmetrical Breaking Capacityi. Asymmetrical Breaking Capacityj. Making Currentk. Arcing Durationl. Make Timem. Operating Duty
Contents
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2. Terminology:
n. Load Current Interruption
o. Interruption of Induction Current (Fault
Currents, small, inductive current)
p. Interruption of capacitive Currents
q. Asynchronous switching
r. Auto Reclosure
s. Delayed Current Zero
t. Fault Making
u. Evolving faults.
Contents
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3. Circuit Breaker Arcs
a. Plasma and Thermal Ionisation (Substance i.e.solid liquid, Gas, Plasma)
b. Ionisation Due to collision of Electronsc. Deionizationd. Properties of the Arce. Striking the Arcf. External Characteristics of the Arcg. Arc stability.h. Dynamic Arc characteristicsi. The A.C Arcj. General Mathematical Arc Modelk. The Mayr Arc equationl. The Cassie Arc equation
Contents
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3. Circuit Breaker Arcs
m. Application of Arc Models.
m1. Pre-zero current (low Arc Resistance)
m2. Post-zero current (High Arc Resistance)
Contents
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4. SF6 Switchgear
a. Arc Interruption is SF6
al . Physical & Chemical Properties
a2. Arc Extinction is SF6
a3. Nozzle Design
a4. Arc Extinction Parameters.
a5. Throat Blocking)
Contents
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4. SF6 Switchgear
b. SF6 Circuit Breaker
bl. Arc chamber; General
b2. Double pressure Arc chamber
b3. Circuit Breaker Type. (Live Tank & Dead)
c. SF6 switching Isolators & other equipment.
cl. Switching Isolators.
c2. Current Transformers
Contents
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5. Air Blast Circuit Breakers.
a. Arc extension
b. Pressurised Head- Atmospheric Head, Air Blast C.B
b1. Constructions.
b11. Auxiliary Chambers.
b12. Tripping/Closing resistors.
b13. Auxiliary Equipment.
Contents
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6. Oil Circuit Breaker
a. Generalb. Bulk-Oil circuit Breakers. c. Minimum Oil Circuit Breaker.
7. Special Purpose Circuit Breakers & Isolators.
a. Air Blast Breakers with transverse air Jet b. Water circuit Breakersc. Pantograph Isolator
Contents
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8. D.C Circuit Breakers.
a. Producing of current zero (Four different methods)
9. Circuit Breakers requirement.
a. Current Interruption
b. Recovery voltage withstand.
c. Recovery voltages calculation by current Injection Techniques
c1. Current injection sequence.
c2. Examples of current Injection
d. Arc theory in short-line fault calculations
Contents
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10. Switchqear Testinq
a. High voltage TYPE TESTS (IEC-56-4)
al. Lightning Impulse Testsa2. Switching Impulse test.a3. Power-Frequency voltage tests
b. Short circuit current TYPE TESTS.b1. Short-time current b2. Breaking currentb3. Transient Restriking b4. Load switchingb5. Earthing Condition b6 Latchingb7. Contact Conditionb8. Critical current
Contents
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c. Type tests related to service conditions
c1. Short line fault
c2. Asynchronous switching
c3. Close loop switching
c4. Transformer magnetisting current switching
c5. Capacitance current switching
Contents
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d. Miscellaneous TYPE tests.
d1. Mechanical
d2. Climatic Conditions
d3. Geographical Conditions
d4. Thermal
Contents
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e. Testing Equipment
e1. Generators and Transformers
e2. Part testing
e2.1 Single phase testing
e2.2 Unit testing
Contents
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11. Synthetic Testing
f1. Principles of synthetic testing
f2. Skeats Circuit
f3. Parallel Injection test circuit
f4. Series Injection test circuit
Contents
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12. Substation Layout and Design
a. Introduction
b. Basic Requirements
b1. System security
b2. Flexibility of operation
b3. Maintenance Facilities
b4. Protection Facilities
b5. Site-area & location
b6. Cost
Contents
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12. Substation Layout and Design
c. Busbar Configuration
c1. Single busbarc2. Duplicate Busbarc3. Duplicate Back to Backc4. Transfer Busbarc5. 1&1/2 Circuit Breaker Arrangementc6. Mesh Arrangementc7. By Pass Facilities.c8. Location of current transformersc9. Indoor or Outdoor substationc10. Segregatione11. Phase-segregated & Insulated phase Busbar.
Contents
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12. Substation Layout and Design
d. Substation Earthing.
d1. Earth Resistivity
d2. Design of earth meshes.
Contents